In the Introduction, a simple recipe was given for building a beowulf.
In many cases this recipe will work just fine. In others, it will fail
miserably and expensively. How can one tell which is which? Better
yet, how can one avoid making costly mistakes and design an
affordable beowulf that will work efficiently on your particular
set of problems?

By learning, of course, from the mistakes and experience and wisdom of
others. This is presumably why you are reading this book. Although
beowulf design isn't impossibly complex - beowulfs have been built by
high school students, hobbyists, scientists and many others without
anything like a degree in systems or network engineering - neither is
it terribly simple. It is therefore useful to present a brief overview
of beowulf design before we get into the nitty-gritty details that make
up much of the next three parts.

Let's begin by setting out a more complex recipe for building a beowulf.